He disproved Galen's assertion that blood moves through invisible pores and argued that it travels from the heart to the lungs through the veins and arteries, just as the canals of Venice bring provisions to the city.
Dia membantah pendapat Galen yang mengatakan bahwa darah mengalir melalui pori-pori tak terlihat dan menyataan bahwa darah bergerak dari jantung ke paru-paru melalui pembuluh dan arteri. Persis seperti kanal di Venice membawa barang-barang kebutuhan ke kota.